/* px em rem  等长度单位的演示 */

html{
    font-size: 65%;/* 16px * 0.625 = 10px */
}
/* body{
    font-size: 10px;
} */
.value_px{
    font-size: 32px;
}
.value_em{
    font-size: 2em;
}
.value_rem{
    font-size: 2rem;
}


/* 颜色值 */
.color_name{
    color: red;
}
.color_hex{
    color: #00ff00;
}
.color_fun{
    color: rgb(0,0,255);
}
/* 图片url属性 */
.img_url{
    width: 393px;
    height: 105px;
    background-image: url("2.jpg");
    border: 1px solid;
}

/* 常见文字属性 */
.font_demo{
    /* font: 400; */
    color: red;
    font-family: 微软雅黑, sans-serif;
    font-size: 20px;
    font-style: italic;
    font-weight: normal;
}

/* 常见文本样式属性 */
.text_demo{
    font-size: 2em;
    border: 1px solid black;
    width: 50rem;
    height: 10rem;
    text-align: center;
    line-height: 10rem;
    text-decoration: line-through;
    text-indent: 3rem;
    letter-spacing: 1rem;
    word-spacing: 2rem;
}

/* 列表样式属性 */
ul{
    font-size: 2rem;
}

.list_demo1{
    list-style: circle inside;
}
.list_demo2{
    list-style: none;
}
.list_demo3{
    list-style-image: url(20201124032511.png);
    list-style-type: none;
    list-style-position: inside;
}
.list_demo4{
    list-style: none url(20201124032511.png) inside;
}

/* 背景样式属性 */
.bg_box{
    border: 1px solid red;
    width: 40rem;
    height: 20rem;
}
.bg_demo1{
    background-color:coral;
}
.bg_demo2{
    background-image: url(20201124032511.png);
    
}
.bg_demo3{
    background-image: url(20201124032511.png);
    /*  background-repeat: no-repeat; */
    /* background-repeat: repeat-y; */
    background-repeat: repeat-x;
} 
.bg_demo4{
    background-image: url(20201124032511.png);
    background-repeat: no-repeat;
    background-position:  center center;
}
.bg_demo5{
    background-image: url(20201124032511.png);
    background-repeat: no-repeat;
    background-position: top right;
    background-attachment: fixed;
}
.bg_demo6{
    background: #00ff00 url(20201124032511.png) repeat-x top right fixed;
}